"If you were here, I could deceive you, and if you were here, you would believe"
It applies to the end of the movie, Sixteen Candles, in the sense that Jake no longer loves Caroline, and the lyrics would be referencing her, since she is not there.
"do not want a part of this anymore"
If Caroline was there, he could deceive her by pretending to still love her, but no longer wants to be part of that relationship.
"If you were here, I could deceive you, and if you were here, you would believe"
It applies to the end of the movie, Sixteen Candles, in the sense that Jake no longer loves Caroline, and the lyrics would be referencing her, since she is not there.
"do not want a part of this anymore"
If Caroline was there, he could deceive her by pretending to still love her, but no longer wants to be part of that relationship.
He's right where he wants to be, with Samantha.